Abstract: A lithographic apparatus applies a pattern repeatedly to target portions across a substrate. Prior to applying the pattern an alignment sensor measures positions of marks in the plane of the substrate and a level sensor measures height deviations in a direction normal to the plane of the substrate. The apparatus applies the pattern to the substrate while positioning the applied pattern using the positions measured by the alignment sensor and using the height deviations measured by the level sensor. The apparatus is further arranged to calculate and apply corrections in the positioning of the applied pattern, based on derivatives of the measured height deviations. The corrections may be calculated on an intrafield and/or interfield basis. The corrections may be based on changes between the observed height deviations and height deviations measured previously on the same substrate.

Abstract: Disclosed is an apparatus and method for performing a measurement operation on a substrate in accordance with one or more substrate alignment models. The one or more substrate alignment models are selected from a plurality of candidate substrate alignment models. The apparatus, which may be a lithographic apparatus, includes an external interface which enables selection of the substrate alignment model(s) and/or alteration of the substrate alignment model(s) prior to the measurement operation.

Abstract: A lithography system configured to apply a pattern to a substrate, the system including a lithography apparatus configured to expose a layer of the substrate according to the pattern, and a machine learning controller configured to control the lithography system to optimize a property of the pattern, the machine learning controller configured to be trained on the basis of a property measured by a metrology unit configured to measure the property of the exposed pattern in the layer and/or a property associated with exposing the pattern onto the substrate, and to correct lithography system drift by adjusting one or more selected from: the lithography apparatus, a track unit configured to apply the layer on the substrate for lithographic exposure, and/or a control unit configured to control an automatic substrate flow among the track unit, the lithography apparatus, and the metrology unit.

Abstract: A method including determining a position of a first pattern in each of a plurality of target portions on a substrate, based on a fitted mathematical model, wherein the first pattern includes at least one alignment mark, wherein the mathematical model is fitted to a plurality of alignment mark displacements (dx, dy) for the alignment marks in the target portions, and wherein the alignment mark displacements are a difference between a respective nominal position of the alignment mark and measured position of the alignment mark; and transferring a second pattern onto each of the target portions, using the determined position of the first pattern in each of the plurality of target portions, wherein the mathematical model includes polynomials Z1 and Z2: Z1=r2 cos(2?) and Z2=r2 sin(2?) in polar coordinates (r, ?) or Z1=x2?y2 and Z2=xy in Cartesian coordinates (x, y).

Abstract: A method of measuring a parameter of a lithographic process, the method including: illuminating a diffraction measurement target on a substrate with radiation, the measurement target including at least a first sub-target, at least a second sub-target and at least third sub-target, wherein the first, second and third sub-targets each include a periodic structure and wherein the first sub-target, second sub-target and third sub-target each have a different design and wherein at least two of the sub-targets are respectively designed for determination of a different lithographic process parameter; and detecting radiation scattered by the at least two sub-targets to obtain for that target a measurement representing the different parameters of the lithographic process.

Abstract: A reticle is loaded into a lithographic apparatus. The apparatus performs measurements on the reticle, so as to calculate alignment parameters for transferring the pattern accurately to substrates. Tests are performed to detect possible contamination of the reticle or its support. Either operation proceeds with a warning, or the patterning of substrates is stopped. The test uses may use parameters of the alignment model itself, or different parameters. The integrity parameters may be compared against reference values reflecting historic measurements, so that sudden changes in a parameter are indicative of contamination. Integrity parameters may be calculated from residuals of the alignment model. In an example, height residuals are used to calculate parameters of residual wedge (Rx?) and residual roll (Ryy?). From these, integrity parameters expressed as height deviations are calculated and compared against thresholds.

Abstract: Disclosed is an apparatus and method for performing a measurement operation on a substrate in accordance with one or more substrate alignment models. The one or more substrate alignment models are selected from a plurality of candidate substrate alignment models. The apparatus, which may be a lithographic apparatus, includes an external interface which enables selection of the substrate alignment model(s) and/or alteration of the substrate alignment model(s) prior to the measurement operation.

Abstract: A lithographic apparatus applies a pattern repeatedly to target portions across a substrate. Prior to applying the pattern an alignment sensor measures positions of marks in the plane of the substrate and a level sensor measures height deviations in a direction normal to the plane of the substrate. The apparatus applies the pattern to the substrate while positioning the applied pattern using the positions measured by the alignment sensor and using the height deviations measured by the level sensor. The apparatus is further arranged to calculate and apply corrections in the positioning of the applied pattern, based on derivatives of the measured height deviations. The corrections may be calculated on an intrafield and/or interfield basis. The corrections may be based on changes between the observed height deviations and height deviations measured previously on the same substrate.

Abstract: A lithography system configured to apply a pattern to a substrate, the system including a lithography apparatus configured to expose a layer of the substrate according to the pattern, and a machine learning controller configured to control the lithography system to optimize a property of the pattern, the machine learning controller configured to be trained on the basis of a property measured by a metrology unit configured to measure the property of the exposed pattern in the layer and/or a property associated with exposing the pattern onto the substrate, and to correct lithography system drift by adjusting one or more selected from: the lithography apparatus, a track unit configured to apply the layer on the substrate for lithographic exposure, and/or a control unit configured to control an automatic substrate flow among the track unit, the lithography apparatus, and the metrology unit.

Abstract: A reticle is loaded into a lithographic apparatus. The apparatus performs measurements on the reticle, so as to calculate alignment parameters for transferring the pattern accurately to substrates. Tests are performed to detect possible contamination of the reticle or its support. Either operation proceeds with a warning, or the patterning of substrates is stopped. The test uses may use parameters of the alignment model itself, or different parameters. The integrity parameters may be compared against reference values reflecting historic measurements, so that sudden changes in a parameter are indicative of contamination. Integrity parameters may be calculated from residuals of the alignment model. In an example, height residuals are used to calculate parameters of residual wedge (Rx?) and residual roll (Ryy?). From these, integrity parameters expressed as height deviations are calculated and compared against thresholds.

Abstract: Estimating model parameters of a lithographic apparatus and controlling lithographic processing by a lithographic apparatus includes performing an exposure using a lithographic apparatus projecting a pattern onto a wafer. A set of predetermined wafer measurement locations is measured. Predetermined and measured locations of the marks are used to generate radial basis functions. Model parameters of said substrate are calculated using the generated radial basis functions as a basis function across said substrate. Finally, the estimated model parameters are used to control the lithographic apparatus in order to expose the substrate.

Abstract: A lithographic apparatus includes apparatus for measuring the alignment of an object. The measuring apparatus includes a plurality of alignment sensors, each including an alignment detector for measuring the position of an alignment mark over an alignment detection area. The measuring apparatus further includes a leveling sensor for measuring the height and/or tilt of an object in a leveling sensor detection area, and a feed-forward connection between said leveling sensor and said alignment sensors.